From: Alexander Usyskin <alexander.usyskin@xxxxxxxxx> commit 740c0a57b8f1e36301218bf549f3c9cc833a60be upstream. The MEI bus has a special behavior on suspend it destroys all the attached devices, this is due to the fact that also firmware context is not persistent across power flows. If watchdog on MEI bus is ticking before suspending the firmware times out and reports that the OS is missing watchdog tick. Send the stop command to the firmware on watchdog unregistered to eliminate the false event on suspend. This does not make the things worse from the user-space perspective as a user-space should re-open watchdog device after suspending before this patch. Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Alexander Usyskin <alexander.usyskin@xxxxxxxxx> Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx> Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210124114938.373885-1-tomas.winkler@xxxxxxxxx Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx> Signed-off-by: Wim Van Sebroeck <wim@xxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/watchdog/mei_wdt.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/watchdog/mei_wdt.c +++ b/drivers/watchdog/mei_wdt.c @@ -390,6 +390,7 @@ static int mei_wdt_register(struct mei_w watchdog_set_drvdata(&wdt->wdd, wdt); watchdog_stop_on_reboot(&wdt->wdd); + watchdog_stop_on_unregister(&wdt->wdd); ret = watchdog_register_device(&wdt->wdd); if (ret) {
